=== modified file 'gcc/doc/invoke.texi'
@@ -8718,6 +8718,10 @@ through which the instruction may be pip
The maximum number of best instructions in the ready list that are considered
for renaming in the selective scheduler. The default value is 2.
+@item sms-min-sc
+The minimum value of stage count that swing modulo scheduler will
+generate. The default value is 2.
+
@item max-last-value-rtl
The maximum size measured as number of RTLs that can be recorded in an expression
in combiner for a pseudo register as last known value of that register. The default
=== modified file 'gcc/modulo-sched.c'
@@ -1222,9 +1222,10 @@ sms_schedule (void)
PS_STAGE_COUNT(ps) = stage_count;
}
- /* Stage count of 1 means that there is no interleaving between
- iterations, let the scheduling passes do the job. */
- if (stage_count <= 1
+ /* The default value of PARAM_SMS_MIN_SC is 2 as stage count of
+ 1 means that there is no interleaving between iterations thus
+ we let the scheduling passes do the job in this case. */
+ if (stage_count < (unsigned) PARAM_VALUE (PARAM_SMS_MIN_SC)
|| (count_init && (loop_count <= stage_count))
|| (flag_branch_probabilities && (trip_count <= stage_count)))
{
=== modified file 'gcc/params.def'
@@ -344,6 +344,11 @@ DEFPARAM(PARAM_SMS_MAX_II_FACTOR,
"sms-max-ii-factor",
"A factor for tuning the upper bound that swing modulo scheduler uses for scheduling a loop",
100, 0, 0)
+/* The minimum value of stage count that swing modulo scheduler will generate. */
+DEFPARAM(PARAM_SMS_MIN_SC,
+ "sms-min-sc",
+ "The minimum value of stage count that swing modulo scheduler will generate.",
+ 2, 1, 1)
DEFPARAM(PARAM_SMS_DFA_HISTORY,
"sms-dfa-history",
"The number of cycles the swing modulo scheduler considers when checking conflicts using DFA",